A proportion such as the one shown can also be written in the form 2:3 and 3:4. The inside terms (3 and 3) are called the means. The outside terms(2 and 4) are called the extremes. The product of the means and extremes can be used to solve proportion problems. In a true proportion the cross product are equal. To figure out the cross products you multiply the the means and the extremes and if they equal the same they are true. When one term of the proportion is unknown you use cross multiplying to find your first part. Once you have you number answer multiply the number and the letter and put the number before the letter.
(Third problem in picture)
The goal of the Bartlesville City Library is to have 2 books in stock for every 5 residents. The most recent census shows that the population is 12,455.Find the total number of books that the library should have to meet the goal.
In a true proportion the cross product are equal. To figure out the cross products you multiply the the means and the extremes and if they equal the same they are true.
When one term of the proportion is unknown you use cross multiplying to find your first part. Once you have you number answer multiply the number and the letter and put the number before the letter.
(Third problem in picture)
The goal of the Bartlesville City Library is to have 2 books in stock for every 5 residents. The most recent census shows that the population is 12,455. Find the total number of books that the library should have to meet the goal